Liquid solution of thiocarbanilide



Patented Nov. 6, 192$.

omen STATES.

HAROLD GRAY;

rArsur OFFICE.

OF AKRON, OHIO, ASSIGNOR TO THE B. F. GOODRICE COMPANY, OF NEW YORK, N. Y., A CORPORATION 01? NEW YORK.

LIQUID SOLUTION OF THIOCARBANILIDE.

7 No hrawing.

i will contain a higher percentage of thiocarbanilide than heretofore obtainable and tor which the thiocarbanilide will not be permatemperature is lowered.

nently separated out at low temperatures.

Thiocarbanilide has been restricted in its For certainpurposes it has been heretofore proposed to dissolve thiocarbanilide with orthotoluidine which however is able to hold in solution at normal temperatures but from 3 to 4% otthis material and from which solutionitis readily crystallized out as the The purpose ot-the present invention is to provide. a composition comprising: thiocarbanilide in solution which will contain relativelv high percentages ct thiocarbanilide and from which solution the thiocarbanilide will not he separated or crystallized out upon lowering" the temperature to C. or lower.

Experiments have shownthat the amines are solvents for thiocarbanilide only to a small degree, aniline being capable of dissolving from 2 to 3% of thiocarbanilideat ordinary temperatures. l have discovered however if two or more distinctly different amines are admired and employed as a solentv fo-r'thiocarbanilide that a greatly in creased percentage of thiocarbanilide may be maintained in solution than any one of these amines singly will maintain. This remarkable property of a mixture of several amines isanalagous to the marked change inrnelt in; points which is brought about by the alloying of a plurality of metals and no explanation of the principle underlying this.

phenomenon has been determined. In general, l have found that an admixture of a rnonamine and a diamine give the mostsatisfactory results but I also find that admin t-uresv of two or more distinctly dillerent 'inonamines are also eflicient solvents for thiocarbanilide.

a liquid and solid'amine is capable of dis-' solving and holding in solution larger per- Application filed A ril as,

i927. Serial No. 187,416.

centages of thiocarbanilide than is the liquid amine alone. A wide variety of amines may however be employed 21S W1ll be evident from the more detailed description hereinafteriven ta I 'lhefollo-wmg specific examples are illustrative of the general principles hereinabove set forth: v

EwampZe J.ll. liquid solution. of thiocarbanilidewas prepared. by admixing together 33 parts by weight of aniline, 26 parts by Weight of dimethyl para-phenylene diamine and 40 parts. of thiccarbanilide. The admixture is heated on a steam bath, or otherwise,

at temperatures ranging from 100 C. to

I 120 C. until a complete solution is obtained, the time of neatlng depending upon the size of the batch treated and generally ranging from 1 to 2 hours, altho shorter times are till ever become somewhat mushy at these ere trernely low temperatures, but it regains its clear liquid characteristics upon the tempera ture being raised. This is a very important property of this solution since it-is important that low. temperatures encountered in ship pingduring the winter season shouldnot cause the thiocarbanilide to be permanently":

separated out of solution, as is the casewith orthotoluidine solutions of thiocarbanilide hereto-fore employed.

maining liquid even at the low temperatures hereinabove referred to has been prepared from the following ingredients: 'llhiocar'-- banilide 60 parts by weight; dimethyl para: phenylen e diamine parts; aniline 503mm; xylidine 30 parts. These materials are-admixed and heated as in the previous example. The product at normal temperatures is a clear dark brown liquid having the appearance of the solution of the prior example. Upon re ducing the temperature to below zero even as low as -40 C. to (3., the material, alt-ho viscous. still retains its liquid characteristics.

Ewample 3.-In the previous example monamines and diamines have been conjointly' employed in the preparation of the thioearbanilide solutions. I find however that admixtures of monamines also produce similar compositions. Thus, 25 parts by weight of thioearbanilide, 30 parts of aniline, 30 parts of orthotoluidine and 15 parts of paratoluidiue were admixed and subjected to heat at temperatures ranging from 80 C, to 100 C. until a clear liquid solution was formed. As in the previous examples, the time of heating varies with the size of the batch. Continued heating after the materials are completely liquefied is not however detrlmental to the resulting product and may in certa n cases be beneficial. There is formed in tlns process a clear brownish liquid from which the thioearbanilide does not separate out even at extremely low temperatures.

The preceding specific examples are suflicient to illustrate the principles of the present invention which however is not restricted either to the substances mentioned or to the proportions given. Thus, it has been found that the proportions of the above examples may be widely varied and that wherever two or more of the amines are admixed together in any proportion they have a greater solvent capacity for thioearbanilide than does either of the amines alone. Moreover, other combinations of amines may be employed as solvents for thioearbanilide. Thus, xylidine may replace the aniline of Example 1 and thefollowing amines have been employed in varying proportions and in numerous combinations of the character hereinabove described to give satisfactory solutions: pyridine, a-naphthylamine, p-phenylene diamine, m toluene diamine, and m-phenylene diamine.

The above indicated compositions of matter comprising solutions of thioearbanilide and amines are useful in the industrial arts in numerous operations but particularly as flotation reagents in the eparation of metals from the ore pulp in the flotation processes commonly employed to effect this result. Where used for this purpose, they have the advantage of containing a much higher percentage of the active flotation reagent, namely thioearbanilide, preferably of the order of from 25 to 40 per cent, than solutions of thioearbanilide heretofore available and the further property that the thioearbanilide will not permanently separate out from the solution when the material is exposed to extremely low temperatures a condition commonly encountered during the shipment and the storage of such materials.

It will be obvious that numerous variations and modifications not herein indicated may be made in the compositions herein described without departing from .the principles of this invention, and I therefore do not purpose wholly to limit the scope of the claims hereto appended except as may be necessitated by the prior art.

I claim:

1. A composition of matter comprising a liquid solution of thioearbanilide and a plurality of (lifl'erentamines.

2. A composition of matter comprising a liquid solution of thioearbanilide, a monamine and a diamine.

3. A composition of matter comprising a liquid solution of thioearbanilide and two different amines, one of which is a liquid.

4. A composition of matter comprising a liquid solution of thioearbanilide and two or more amines of different empirical formulas, at least one of which is a liquid.

5. A composition of matter comprising a solution of thioearbanilide and three amines, one of which is a liquid.

, 6. A composition of matter comprising thioearbanilide, a liquid monamine and a diamine.

7. Av composition of matter comprising thioearbanilide and two or more different amines, at least one of which is a liquid monamine.

8. A composition of matter comprising thioearbanilide and a plurality of amlnes including a liquid monamine and dimethyl paraphenylene diamine.

9. A composition of matter comprising thioearbanilide and a plurality of ammes including aniline and a diamine.

10. A composition of matter comprising thioearbanilide and a plurality of amines including anilinev and dimethyl para-phenylene diamine.

11. A composition of matter comprising thioearbanilide and a plurality of amines including xylidine.

12. A composition of matter comprising thioearbanilide and a plurality of amines including xylidine and a diamine.

13. A composition of matter comprising thioearbanilide and a pluralityof amines including xylidine and dimethyl para-phenyl diamine.

14. A composition of matter comprising thioearbanilide and a plurality of amines including aniline, xylidine and a diamine.

15. A composition of 'matter comprising thioearbanilide and a plurality of amines including aniline, xylidine and dimethyl paraphenylene diamine.

16. A composition of matter comprising a clear liquid solution at normal temperatures of thioearbanilide and a. plurality of different amines, which solution retains its fiuigity at temperatures somewhat below 0 17. A composition of matter comprising a clear liquid solution at normal temperatures of thiocarbanilide and a plurality of different amines, from which solution thioearbanilide is not permanently separated out at tem'peraper cent of thiocarbanilide in solution at C. tures somewhat below 0 C.. 20. As a new composition of matter, a

18. As a new composition of matter a clear fluid admixture of thiocarbanilide and a pluliquid solution of thiocarbanilide and a plurality of amines containing from 25 to 40 per 5 rality of different amines containing 25 to 40 cent of t-hiocarbanilide at normal temperaper cent of thiocarbanilide at normal tempertnres. atures. 1 A r In witness whereof I have hereunto set my 1 19. As anew composition of matter, a clear hand this th day of April, 1927. V

quid solution of thiocarbanilide and a. p1u

a ity of diflerent amines containing to HAROLD GRAY. 

